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PurposeEvaluation of mRNA and microRNA (miRNA) expression in epithelium and stroma of patients with keratoconus.MethodsThe epithelium and stroma of eight corneas of eight patients with keratoconus and eight corneas of eight non-keratoconus healthy controls were studied separately. RNA was extracted, and mRNA and miRNA analyses were performed using microarrays. Differentially expressed mRNAs and miRNAs in epithelial and stromal keratoconus samples compared to healthy controls were identified. Selected genes and miRNAs were further validated using RT-qPCR.ResultsWe discovered 170 epithelial and 1498 stromal deregulated protein-coding mRNAs in KC samples. In addition, in epithelial samples 180 miRNAs and in stromal samples 379 miRNAs were significantly deregulated more than twofold compared to controls. Pathway analysis revealed enrichment of metabolic and axon guidance pathways for epithelial cells and enrichment of metabolic, mitogen-activated protein kinase (MAPK), and focal adhesion pathways for stromal cells.ConclusionsThis study demonstrates significant differences in the expression and regulation of mRNAs and miRNAs in the epithelium and stroma of Patients with KC. Also, in addition to the well-known target candidates, we were able to identify further genes and miRNAs that may be associated with keratoconus. Signaling pathways influencing metabolic changes and cell contacts are affected in epithelial and stromal cells of patients with keratoconus.  相似文献   
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Introduction: Drug overdose deaths increased approximately 30% from 2019 to 2020 in the United States. Examining rates by demographic and social determinants of health characteristics can identify disproportionately affected populations and inform strategies to reduce drug overdose deaths.Methods: Data from the State Unintentional Drug Overdose Reporting System (SUDORS) were used to analyze overdose death rates from 2019 to 2020 in 25 states and the District of Columbia. Rates were examined by race and ethnicity and county-level social determinants of health (e.g., income inequality and treatment provider availability).Results: From 2019 to 2020, drug overdose death rates increased by 44% and 39% among non-Hispanic Black (Black) and non-Hispanic American Indian or Alaska Native (AI/AN) persons, respectively. Significant disparities were found across sex, age, and racial and ethnic subgroups. In particular, the rate in 2020 among Black males aged ≥65 years (52.6 per 100,000) was nearly seven times that of non-Hispanic White males aged ≥65 years (7.7). A history of substance use was frequently reported. Evidence of previous substance use treatment was lowest for Black persons (8.3%). Disparities in overdose deaths, particularly among Black persons, were larger in counties with greater income inequality. Opioid overdose rates in 2020 were higher in areas with more opioid treatment program availability compared with areas with lower opioid treatment availability, particularly among Black (34.3 versus 16.6) and AI/AN (33.4 versus 16.2) persons.Conclusions and Implications for Public Health Practice: Health disparities in overdose rates continue to worsen, particularly among Black and AI/AN persons; social determinants of health, such as income inequality, exacerbate these inequities. Implementation of available, evidence-based, culturally responsive overdose prevention and response efforts that address health disparities impacting disproportionately affected populations are urgently needed.  相似文献   
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La Crosse virus (LACV) is a major cause of pediatric encephalitis and aseptic meningitis in the Midwestern, Mid-Atlantic, and Southern United States, where it is an emerging pathogen. The LACV Gc glycoprotein plays a critical role in the neuropathogenesis of LACV encephalitis as the putative virus attachment protein. Previously, we identified and experimentally confirmed the location of the LACV fusion peptide within Gc and generated a panel of recombinant LACVs (rLACVs) containing mutations in the fusion peptide as well as the wild-type sequence. These rLACVs retained their ability to cause neuronal death in a primary embryonic rat neuronal culture system, despite decreased replication and fusion phenotypes. To test the role of the fusion peptide in vivo, we tested rLACVs in an age-dependent murine model of LACV encephalitis. When inoculated directly into the CNS of young adult mice (P28), the rLACV fusion peptide mutants were as neurovirulent as the rLACV engineered with a wild-type sequence, confirming the results obtained in tissue culture. In contrast, the fusion peptide mutant rLACVs were less neuroinvasive when suckling (P3) or weanling (P21) mice were inoculated peripherally, demonstrating that the LACV fusion peptide is a determinant of neuroinvasion, but not of neurovirulence. In a challenge experiment, we found that peripheral challenge of weanling (P21) mice with fusion peptide mutant rLACVs protected from a subsequent WT-LACV challenge, suggesting that mutations in the fusion peptide are an attractive target for generating live-attenuated virus vaccines. Importantly, the high degree of conservation of the fusion peptide amongst the Bunyavirales and, structurally, other arboviruses suggests that these findings are broadly applicable to viruses that use a class II fusion mechanism and cause neurologic disease.  相似文献   
86.
Effectively managing and optimizing the value of the patent portfolio is a major challenge for many firms, especially those in knowledge intensive industries, such as the pharmaceutical, biotechnological and chemical industry. However, insights on effective patent portfolio strategies are rare. Therefore, in this article we investigate in detail how firms successfully manage and optimize their patent portfolios to increase their overall competitiveness. We discover that successful patent portfolio management is rooted in managing the patents along their life cycles. Based on the findings of ten case studies, we develop a holistic patent life cycle management model reflecting five distinctive phases of patent management: explore, generate, protect, optimize and decline. We conclude with how our findings can be used in practice.  相似文献   
87.
A growing body of evidence suggests that food insecurity is associated with adverse mental health outcomes such as depression and anxiety. In this study, the relationship between food insecurity and depression was examined using data from the 2005–2016 National Health and Nutrition Examination Survey (NHANES). Food insecurity was assessed with the 18-item United States Food Security Survey Module with zero affirmative responses indicating high food security, 1 or 2 affirmative responses indicating marginal food security, and ≥3 affirmative responses indicating food insecurity. Depression was assessed with the Patient Health Questionnaire-9 with scores ≥10 indicating depression. Data were analyzed from 28,448 adult participants aged 20 or older. Food insecurity was present in 19.2% of the sample population (n = 5452). Food security status was significantly associated with gender, race, education level, marital status, smoking status, and BMI (Rao-Scott chi-square, p < 0.05). Fully food secure and very low food security adults experienced depression at a rate of 5.1% and 25.8%, respectively (Rao-Scott chi-square, p < 0.0001). Participants with very low food security had a significantly greater odds of depression than food secure adults, OR = 3.50 (95% CI: 2.98, 4.12). These findings suggest that food insecurity is a significant risk factors for depression in US adults over 20 years of age. To address this issue in our citizenry, police initiatives and public health interventions addressing both food access and mental health should be prioritized.  相似文献   
88.
BackgroundSouth Africa’s healthcare system has a multitude of pre-existing challenges prior to the onset of the coronavirus disease 2019 (COVID-19) pandemic, ranging from reduced number of staff, lack of resources and units being at overcapacity both in the adult and paediatric populations. The neonatal intensive care units (NICUs) require a team approach to ensure best practice with vulnerable infants, but little is known about how the onset of the COVID-19 pandemic and the resultant lockdown restrictions impacted the feeding practices within the NICU.ObjectivesThis study aimed to explore the impact that COVID-19 had on the feeding practices within the NICU settings in public hospitals in Gauteng.MethodsA qualitative design was employed with data collected in two NICUs in Gauteng. Data were collected in the form of observations and semi-structured interviews with healthcare workers (HCWs) in the NICU. Data were analysed using inductive thematic analysis.ResultsAlthough the sample size of participants was limited, social distancing proved to be a challenge resulting in mothers and healthcare workers being given restricted access. This had effects on the ability to provide adequate feeding practices and resulted in anxiety for the mothers and mental health challenges for the HCWs when feeding these at-risk infants. A limitation of this study was the use of only two sites.ConclusionCOVID-19 amplified the existing challenges in the NICU. A multidisciplinary and family-centred approach to address feeding challenges is required to offset the challenges resulting from the pandemic and subsequent lockdown.  相似文献   
89.
Timely follow‐up for positive cancer screening results remains suboptimal, and the evidence base to inform decisions on optimizing the timeliness of diagnostic testing is unclear. This systematic review evaluated published studies regarding time to follow‐up after a positive screening for breast, cervical, colorectal, and lung cancers. The quality of available evidence was very low or low across cancers, with potential attenuated or reversed associations from confounding by indication in most studies. Overall, evidence suggested that the risk for poorer cancer outcomes rises with longer wait times that vary within and across cancer types, which supports performing diagnostic testing as soon as feasible after the positive result, but evidence for specific time targets is limited. Within these limitations, we provide our opinion on cancer‐specific recommendations for times to follow‐up and how existing guidelines relate to the current evidence. Thresholds set should consider patient worry, potential for loss to follow‐up with prolonged wait times, and available resources. Research is needed to better guide the timeliness of diagnostic follow‐up, including considerations for patient preferences and existing barriers, while addressing methodological weaknesses. Research is also needed to identify effective interventions for reducing wait times for diagnostic testing, particularly in underserved or low‐resource settings. CA Cancer J Clin 2018;68:199–216 . © 2018 American Cancer Society .  相似文献   
90.
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